Species-isolating mechanisms in a mating system with male mate choice (garter snakes,<i>Thamnophis</i>spp.)
Bibliographic record
Abstract
Reproductive isolation between sympatric taxa can be maintained by specific mate-recognition behaviours or by ecological divergence that reduces interspecific contact during reproduction. Common garter snakes, Thamnophis sirtalis (L., 1758), and plains garter snakes, Thamnophis radix (Baird and Girard, 1853), are sympatric over large areas, but morphological data suggest that the prezygotic isolation between these two species partially breaks down in a severely cold part of their joint range in Manitoba. Courtship trials show that male T. radix court intensely over a narrower range of (higher) ambient temperatures than do male T. sirtalis. Males selectively court females of their own species, but male T. radix are less choosy than male T. sirtalis. Hexane extracts of female skin lipids also elicited species-specific courtship. Although this male preference for species-specific pheromones contributes to species isolation, it is not strong enough to completely separate the two taxa. The absence of hybridization over most of the sympatric range may depend on the timing of mating (early spring, near the hibernation den). Differences between the species in hibernation-site selection and the timing of spring emergence break down in central Manitoba because severely cold winter temperatures force both species together into the few available hibernation (and thus, mating) sites, and the short warm season reduces temporal separation in emergence (and thus, mating) seasons.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".